Over the years, a variety of power or energy sources operating off of heat derived from the oxidation of metallic lithium have been proposed. See, for example, U.S. Pat. No. 3,328,957 issued July 4, 1967 to Rose. In such a system, water and lithium are reacted to produce lithium hydroxide, hydrogen and steam. Elsewhere in the system, the hydrogen generated by the reaction between lithium and water is combined with oxygen to provide additional steam. The steam is then utilized to drive a turbine or the like to provide a source of power.
More recently, somewhat similar systems have been proposed wherein metallic lithium, in the solid phase, is placed within a boiler. When power is desired, the lithium is melted and oxidized with sulfur hexafluoride. The resulting heat vaporizes a working fluid, typically water, in a working fluid chamber in heat exchange relation with the oxidation chamber of the boiler. Again, a turbine may be driven by the working fluid.
While the latter system is effective, it is not without its drawbacks. In the usual case, the system start is initiated by firing a thermal starting device employing aluminum potassium perchlorate. This device is intended to heat the thermal mass of the boiler and the lithium fuel therein to operating temperature. The aluminum potassium perchlorate utilized generates extremely high temperatures, typically in the range of 5400.degree.-8500.degree. F. and must be pelletized and closely packed to propagate ignition of the system. To achieve such, core holes are provided in the lithium which are filled with the aluminum potassium perchlorate and a squib provided within the core hole. The core is then sealed with a lithium plug. Substantial pressures may be generated during the ignition of the aluminum potassium perchlorate requiring high strength of the boiler structure. Moreover, if the aluminum potassium perchlorate, while undergoing oxidation, contacts boiler surfaces it can burn through parts of the boiler damaging the system. It may also burn through or damage nozzles employed to inject sulfur hexafluoride into the reaction mass. Again, damage to the system can occur.
Furthermore, if the squib is not properly placed or otherwise inoperative, initiation of system operation may fail to occur.
The present invention is directed to overcoming one or more of the above problems.
Prior art of possible relevance, in addition to that identified above, includes Chemical Abstracts, Vol. 70, 1969 at page 34, item 120326(c) and the following U.S. Pat. Nos. 3,843,557 issued Oct. 22, 1974 to Fanger et al; 3,909,444 issued Sept. 30, 1975 to Anderson et al; and 4,016,099 issued April 5, 1977 to Wellman et al.